In a system that displays an animated sequence of images, wherein an image of an object or objects moves relative to an image of other objects, a particular problem relates to the generation of screen flicker. This flicker results from a conventional approach of erasing the object at a first location within a screen memory and redrawing the object at a second location. As the object grows larger and/or more complex in shape the time required to erase and rewrite the individual image pixels increases, resulting in a more pronounced screen flicker effect. The presence of screen flicker is objectionable at least for the reason that it prevents a realistic, flicker-free animation sequence from being displayed.
It is therefore an object of the invention to provide method and apparatus for displaying on a display screen a relative movement of a first object to a second object.
It is another object of the invention to provide method and apparatus for displaying on a display screen a relative movement of a first object to a second object without generating a significant amount of screen flicker.